Telephotographic apparatus and the like



H. KNUDSEN TELEPHOTOGRAPHIC APPARATUS AND THE LIKE Dec. 13, 1938.

5 Sheets-Sheet l Filed May 11, 1956,

ATTORNEY Decfr 13, 1938. H. KNUDSEN TELEPHOTOGRAPHIC APPARATUS AND THE LIKE 3 Sheets-Sheet 2 Filed May 11., 1956 mmf,

ATTORNEY Dec. 13, 1938. H. KNUDSEN TELEPHOTOGRAPHIC AP'PARATUS AND THE LIKE 3 Sheets-Sheet 3 Filed May ll, 1936 INVENTOR Waff/ramena ATTORNEY' Patented Dec. 13, 1938 UNITED STATES PATENT OFFICE Hans Knudsen, Streatham, England Application May 11, 1936, Serial No. 79,162 In Great Britain February 17, 1936 13 Claims.

This invention relates to telephotographic apparatus and the like.

It is already known that in the transmission and reception of images or objects by telephotography the perfection of recording and reproduction of such images depends upon the number of elements, picture lines or light beams into which the said images may be analyzed and that the speed of such recording and reproduction depends upon the intensity of the light from which this analysis is made.

The object oi` this invention is to provide improved telephotographic apparatus which will work at a high speed and which will clearly and efficiently record or reproduce pictures or the like, the said apparatus being arranged in a simple and compact manner.

With the above object in view the invention consists in passing through a gate or the like at predetermined speeds a metallic band and a film or the like, said lilm being travelled transversely to the band which latter is provided with a line of slots or apertures, a source of light and light intensifying means being arranged adjacent to the band and over a slot in the gate so that the lm will be scanned minutely during its travel. In the case of recording the light and light intensifying means are arranged above the band which is preferably of an endless type and a light sensitive unit for the conversion of the light beams into electric 'current is arranged below and connected with any usual or convenient amplifying means. In the case. of reproduction the: light actuated by suitably amplified incoming signals and the light intensifying means are arranged above the band so that the images or the like would be reproduced on a travelling sensitized lm by the Varying light intensity which film or rsensitized surface can be developed to provide a master lm or the like to be used in any usual or convenient manner.

The invention still further consists in provid'- ing the gate with a narrow slot of equal or greater length than the width of the iilm and providing in the yband a line of narrow slots at right angles to the said film,'the arrangement being such that the film Will be completely analyzed through the medium of the square formed apertures of the minimum size.

One form of the invention will now be described with reference to the. accompanying drawings in which:

Figure l is a plan of a transmitter or a receiver constructed according to this invention, the light source being removed to show the gate.

Figure 2 is a side View thereof, parts being shown in section such as the light source and the gate;

Figure 3 is a sectional end elevation;

Figure 4 is a section taken through the gate; f

Figure 5 is a cross section taken on the line A-A of Figure 3.

As shown more particularly in Figures 1 to 5, a transmitter or a receiver constructed according to this invention comprises a base I carrying brackets and bearings 2 and 3 supporting, respectively, two shafts 4 and 5 arranged parallel to each other. The shaft 4 hereinafter referred to as the drive shaft 4 is driven by a suitable motor 6 also mounted on the base I. This drive shaft 4 is fitted with a sprocket pulley 'I adapted to drive an endless scanning band 8 which is also carried by a pulley 9 mounted on the other parallel shaft 5. This scanning band 8 which is of metal, preferably steel, is formed adjacent to each side edge with slots I0 for engagement with the teeth II of the sprocket pulley "I so that the said band 8 is driven thereby. This scanning band 8 is also formed with a row of spaced slots i2 preferably of a rectangular shape, the length of the slots I2 being atright angles to the length of the band 8. This band 8 is adapted to pass through a gate or the like I3 mounted between the parallel shafts 4 and 5 and this gate i3 is formed with a scanning slot I4 at right angles to the said parallel shafts 4 and 5. Through this gate I3 and under the scanning band 8 is also adapted to pass a film or the like I5 arranged transversely of the band 8. This film I5 is adapted to be driven in the usual manner by a sprocket wheel I6 mounted on a shaft I'I disposed at right angles to the parallel shafts 4 and 5 and this sprocket shaft I'I'is fitted with a worm wheel I8 which is adapted to gear with the worm I9 secured on the drive shaft 4. Thus the iilm I5 will be driven through the gate I3 at right angles to the scanning band 8. The lm I5 is preferably drawn off a drum, not shown but disposed under the base, by means of the sprocket Wheel Iii and passes under a tension` roller I6 into a receiving drum not shown, as will be well understood. The film will thus pass over a pulley wheel 28 and travel through guides I3 iitted in the gate I3. The base I is formed with apertures to permit of the passage of the film I5 to and from the drums disposed under the base. The shaft I'I is fitted with a pulley 2I to enable the receiving drum to be driven by a belt 22. The gate I3 which comprises upper and lower plates formed with the recessed guides or the like I3 to guide the film I5 and the band 8 is preferably adjustably mounted on a plurality of upright supports 23. A vertical support 23 is preferably arranged at each corner of the substantially square shaped gate member I3 and each pair of supports 23 is slidably mounted on a pair of horizontal guide rods 24 secured at their ends to the bracket bearings 2 and 3 carrying the paralle] shafts 4 and 5. Thus the gate I3 can be adjustably secured longitudinally on the guide rods 24 by suitable screws. On the vertical supporting rods 23 of the gate I3 is adjustably mounted a suitable insulated block or blocks 25 carrying a source of light preferably in the form of a tubular lighting member 25. The block 25 preferably in the form of a pair of members carries this lighting member 25 within a refiector casing 27 of substantially U shape in cross section and the block 25 is adjustably mounted on coiled springs 28 positioned on the vertical supporting rods 23, the adjustment being effected by nuts 29 adapted to screw on screwed ends of the supporting rods 23 and engaging with the block 25. Within the lower open portion of the reflection casing 21 is fitted a lens 3D of any suitable character so that the light from the lamp 25 can be concentrated through the medium of the lens 3G into the slot I4. formed in the gate I3. The lens 30 is of substantially rectangular shape so as to provide a line of light substantially equal to the length of the slot I4 in the gate I3. The lower end of the reiiector casing 2 is preferably loosely fitted with a shroud 3I which is adapted to rest on the gate I3. The tubular lamp 2B is preferably mounted at each end in cylindrical members 32 carried by the block 25 and one of these cylindrical members 32 is perforated at 33 and fitted with a housing 34 connected with an air pipe 35 through which air is pumped by any suitable means to cool the lamp 2B, the air being discharged under the light enclosing shroud 3l resting on the gate and through perforations in the other cylindrical member 32. The air pipe 35 connected with'the lamp housing is also fitted or formed with a jet 3B or jets adapted to impinge air on to the row of the centrally arranged apertures I2 in the metal scanning band 8 so as to clear these of any dust or foreign matter during the travel of the said band 8. The sprocket pulley 'i is preferably formed with acircumferential groove or recess 37 as shown more particularly in Figure 5 to permit of the passage of the air through the said apertures I2 and to facilitate cleaning. The other pulley 5 may also be formed with a circumferential groove 38 to prevent dirt clogging in the apertures I2. It will be seen that a line of light can be focussed to its maximum intensity into the slot I4 by adjusting the lamp carrying blocks 'J5 on the vertical rods 23` through the medium of the coiled springs 28 and the adjusting nuts 29. The slot I4 in the gate i3 is preferably chamfered at 39 so as to permit of the rays of light to pass uninterrupted through the scanning portion of the slot I4 which is of the minimum width. If desired means may be provided to further intensify the light into the gate. For instance mirrors may be arranged at the side of the reflector casing 2'! or longitudinal prisms may be so arranged in the manner to be hereinafter described as to concentrate and deflect all side light from the tubular lamp or lamps on to the lens. The lens and/or condenser may be of any suitable character and may be a single lens or a multiple lens.

The above describes the essential parts of both the transmitter and the receiver. In the case of the transmitter a light sensitive unit such as a photo electric cell 4U is mounted in an insulated block 4I which is also carried below the gate member I3 on the before mentioned vertical rods 23. This photo electric cell 40 is connected with any suitable amplifying means, not shown, for transmission in any convenient and usual manner. It will be seen that the gate member I3, the lamp 25 and light sensitive unit 4U can be adjusted as desired and since a row of right angularly disposed scanning slots I2 are provided in the scanning band 8 any sideways movement of the scanning band 8 will not cut off the light or affect the efficiency of the apparatus. The slots I2 in the metal band 8 are preferably 4/1000 of an inch wide and le of an inch in length and they are arranged in a single central rod in the band 1 inch apart. The mechanical, electrical and optical units of both the transmitting and receiving apparatus are of like form and construction as previously mentioned but for transmitting purposes there is included a specially powerful lamp or lamps and a photo-electric cell, whilst for receiving, the cell is omitted and a neon argon lamp or like variable light source is employed. Both lamps are cooled by a high velocity current of air as previously described. In transmitting use is made of a positive film I5 such as for example as used in cinematography which film is suitable prepared with the matter for transmission. This matter may comprise pictures or illustrations such as cinematograph film with or without sound records or may comprise printed matter, original hand-writing, drawings or the like or may consist of worded messages such as telegrams or letters for direct radio transmission at high speed. In receiving a negative film is used upon which is directly recorded in photographic form the matter transmitted for reception. The band 8 provides a scanning means for analyzing the positive film into linear beams of light when transmitting and for photographing successive linear beamsupon the negative film the light emitted from the neon argon lamp when receiving.

For the purpose of synchronizing the revolution of the motors 6 of the transmitting and receiving devices any suitable form of electrically synchronized motor may be used, preferably arranged to work at 50 cycles per second so that a motor making one revolution per cycle will give 3,000 revolutions per minute. In the preferred construction the sprocket pulley for the film is 3 inches in circumference and the worm and wheel gear has, for example, a ratio of 50 to 1 and is adapted to revolve once per second so that the film is moved across the track of the moving scanning band at a ratio of 3 inches per second. The sprocket pulley for driving the scanning band over the plain pulley is 15 inches in circumference so that the band is carried across the path of the film at the rate of 15 inches or 15 holes per revolution. The central apertures in the band are preferably spaced at 1 inch apart so that in each revolution of the motor 15 holes in the band move across the film. Thus in 50 revolutions per second of the motor the 3 inches of film will be analyzed into 750 light lines per second giving a ratio of 250 light lines per inch of film. In this manner is secured the factor of speed.

For the other factor that is the intensity of the light one or more powerful tubular electric lamps are provided having light intensifying means aspreviouslyor hereinafter described and so that yintensiiied light maybe focussed upon the portion of the rfilm l passing through 'the gate member I3 andfat a point nearest kto the apertures l2 in the moving band 8. This illumihated `portion of the klm is analyzed .byk the scanning band 8 into a series of light beams of powerful intensity which 1in turn actuate the photo-electric cell .or the like da. To obtain the exact position and the requisite focus the blocks 25 carrying the lightand the cell may be moved up or down the upright .supports y23 which latter may be movedalong their supporting rods 24 as required.

In rreception the illuminating lamp on the adjustable block 25 is replaced by a neon argon lamp or other suitable light source provided with reflectors and a condenser and the light variations set up in the neon argon lamp are analyzed into light beams or lines by the band and are received upon the negative lm as photographs line by line accurately placed side by side forming an image of the original picture transmitted without one line overlapping on another, or leaving unexposed lines between the picture element line; by this means a picture can be transmitted and received substantially equal to an ordinary cinematograph nlm.

The described apparatus may be incorporated in any known system of transmitting, amplifying or receiving installation now in general use for radio, telegraphy, telephony or for broadcasting sound o1' television.

It will be seen that the above described apparatus may be employed for various purposes, as one example, it will be particularly advantageous in television. In this case televised matter may be impressed on a film and transmitted by the above apparatus to a number of telephotographic receivers hereinbefore` described situated at various distances from the transmitter and from these receivers the matter can be again broadcast for television. The apparatus will thus act as relays and enhance the scope of television which at the moment cannot be transmitted over long distances. Further topical events which may be cinematographed can be transmitted to all parts of the world to enable further iilms to be made and shown in a very short space of time. Thus such pictures with or without sound can be exhibited in all parts of the world on the same day. The apparatus can be used without alteration for high speed telegraphic purposes and it is particularly den signed for such purposes as well as for other purposes which will be obvious to those skilled in the art.

What I claim is:-

A telephotographic apparatus including a gate formed with a slot, a scanning band formed with scanning apertures movable lengthwise the slot in the gate, a iilm to be scanned movable in the gate, and a light source mounted to direct the rays of light through the slot in the gate, the apertures in the band and the nlm, the scanning band and lm being mounted for movement at approximately right angles to each other and being held in the in constant allel relation, the slot in the gate and the apertures in the band maintaining a constant uniform light distribution to the nlm of invariable area and coniiguration.

2. A telephotographic apparatus including a gate formed with a slot, a scanning band mounted for movement in the gate and formed with apertures of a length transverse the band exceeding the width of the slot inthe gate and of a width longitudinally of the band approximating the width of the slot in the gate, a nlm underlying the band, and a light source dir cting the light rays through the slot in the gate and the apertures in the band to the film, the band and iilm being mounted for movement at approximately right angles to each other and guided within the gate to insure their constant invariable parallel relation during operation, the light admission to the lm being that directed through the area admitted through the slot in the gate and limited by that variation of the aperture inthe band exposed through the slot in the gate.

3. A telephotographic apparatus including a gate formed with a slot, a light source arranged beyond the slot, an endless band moving through the gate and guided thereby, said band being formed with apertures movable longitudinally of the slot in the gate in the movement of the band, said apertures defining with the slot in the gate a restricted aperture having one dimension corresponding to the width of the slot in the gate and the other dimension corresponding to the width o the aperture in the band, said gate being recessed immediately below the band, and a lm traveling in said recess in a direction at right angles to the band.

4. A telephotographic apparatus including a gate formed with a slot, a light source arranged beyond the gate to direct the light rays through said slot, a scanning band and a film supported by and guided in movement in the gate, the band being arranged intermediate the slot in the gate and the film, said band being formed with apertures having a length exceeding that of the width of the slot of the gate and movable lengthwise said slot in the movement of the band, the mounting of the band and lm in the gate maintaining the film and band in constant invariable parallel relation and uniformly spaced from each other and from the slot in the gate, and means for operating the band and iilm.

5. A construction as dened in claim 4, wherein the slot in the gate is at least equal to the width o1 the film.

6. A construction as dened in claim 4, wherein the apertures in the band have a dimension transverse the band exceeding the width of the slot in the gate.

7. A construction as dened in claim 4, wherein the light source is adjustable with respect to the slot in the gate.

8. A construction as defined in claim 4. wherein the means are provided for cooling the source of light.

9. A construction as dened in claim 4, wherein the means for operating the band and lm serves to move the band and iilm at constant invariable uniform relative speeds.

10. A construction as defined in claim 4, wherein the gate is adjustably mounted and comprises a pair of plates formed with guides for the band and for the lm.

11. A telephotographic apparatus including a gate formed with a slot, a light source arranged beyond the gate to direct the light rays through the slot, a scanning band, and a lm supported by and guided in movement in the gate, the band being formed with apertures having a length exceeding that of the width of the slot of the gate and movable lengthwise said slot in the movement of the band, and means for directing a the slot, a scanning band, and a film supported by and guided in movement in the gate, the band being formed with vapertures having a length exceeding that of the width of the slot of the gate and movable lengthwise said slot in the movement of the band, and means for directing a current of air through the apertures in the band at a point beyond the gate to clear said apertures.

13. A telephotographic apparatus including a gate formed with a slot, a light source arranged beyond the gate to direct the light rays through the slot, a scanning band, and a lm supported by and guided in movement in the gate, the band being formed with apertures having a length exceeding that of the width of the slot o1' the gate and movable lengthwise said slot in the movement of the band, and a conduit for directing air under pressure to the light source for cooling the same, said conduit having a jet outlet to be directed through the apertures in the band at a point beyond the gate whereby to clear said apertures of obstruction.

HANS KNUDSEN 

